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Jankunas J Zare RN Bouakline F Althorpe SC Herráez-Aguilar D Aoiz FJ 《Science (New York, N.Y.)》2012,336(6089):1687-1690
When a hydrogen (H) atom approaches a deuterium (D(2)) molecule, the minimum-energy path is for the three nuclei to line up. Consequently, nearly collinear collisions cause HD reaction products to be backscattered with low rotational excitation, whereas more glancing collisions yield sideways-scattered HD products with higher rotational excitation. Here we report that measured cross sections for the H + D(2) → HD(v' = 4, j') + D reaction at a collision energy of 1.97 electron volts contradict this behavior. The anomalous angular distributions match closely fully quantum mechanical calculations, and for the most part quasiclassical trajectory calculations. As the energy available in product recoil is reduced, a rotational barrier to reaction cuts off contributions from glancing collisions, causing high-j' HD products to become backward scattered. 相似文献
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J.M.B. Smith M.SC. PH.D. 《New Zealand veterinary journal》2013,61(5):83-84
Extract In order to utilize spring growth efficiently under a system of grassland farming, a New Zealand dairy farmer endeavours to calve as many cows as possible within a four to six weeks' period. To maintain this calving pattern, herd members must conceive by 70 to 80 days after calving. Consequently normal postparturient uterine involution, together with a minimum of delay in the onset of ovarian activity and oestral cyclicity, is of vital importance. A study of these phenomena may be very rewarding in helping to achieve optimal reproductive efficiency. 相似文献
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John M.B. Smith M.SC. PH.D. 《New Zealand veterinary journal》2013,61(10):210-211
Extract Sir,—A 7-month-old lamb was presented for slaughter, one of a line of 460. The animal was in good condition and, except for a moderately enlarged abdomen, no abnormalities could be detected on ante-mortem examination. 相似文献
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Abstract Extract Sir,—Japanese workers (Matumoto el al., 1965) have examined 388 horse sera from 17 countries including New Zealand and have found evidence of a high incidence of infection with equine rhinopneumonitis virus. The New Zealand material was supplied between 1957 and 1960, by Dr J. D. Manning, then of the National Health Institute, Wellington. 相似文献
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IG Langstaff JS McKenzie WL Stanislawek CEM Reed R Poland SC Cork 《New Zealand veterinary journal》2013,61(3):160-165
AIM: To determine if migratory birds arriving in New Zealand in the Southern Hemisphere spring of 2004 were infected with the highly pathogenic avian influenza (AI) virus, H5N1. METHODS: Cloacal and faecal samples were collected from migratory red knots following their arrival in New Zealand in October 2004. Two species of resident sympatric birds, wrybill and mallard duck, were sampled prior to, and following, the arrival of migratory birds. RESULTS: No AI viruses were isolated from migratory or resident shorebirds. Non-pathogenic AI viruses were isolated from six resident mallard ducks, comprising the endemic subtypes H4 (n=2), H7 (non-pathogenic), H10, and H11 (n=2). CONCLUSIONS: Highly pathogenic AI H5N1 virus was not detected in migratory shorebirds or sympatric water birds in the Firth of Thames, New Zealand, in 2004-2005, despite the possible proximity of migratory birds to outbreaks of the disease in East Asia in 2004. 相似文献